Door latch mechanism



Feb. 18, 1941. R. HEIZMANN DOOR LATCH MECHANISM Filed March 22, 1939 2Sheets-Sheet 1 INVElVTOR mi 71,5 15

A TTORNEYS.

Feb. 18, 1941. R. HEIZMANN 2,231,903

DOOR LATCH MECHANISM Filed March 22, 1939 2 Sheets-Sheet 2 WITNESSES: IN VEN TOR Z/ 5 Raymond mi mann,

BY W Patented Feb. 18, 1941 UNITED STATES PATENT OFFICE noon LATCHMECHANISM Raymond Heizmann, shillington, Pa. Application March 22, 1939,Serial No. 263,345

12 Claims. (01. 70-153) Thisinvention relates to door latch mechanismand it is concerned more particularly with latch mechanism of the typewherein the latch bolt is actuated by a spindle which passes through thedoor and which is fitted at opposite ends with manipulating grasp knobs.

In connection with latch mechanism of the type referred to, I aim tomake it possible to set the latch bolt so that it cannot be operated bymeans of the outside knob, without precluding its operation at any timeby means of the inside knob.

above advantages in door latch mechanism which is reliable in operation;which embodies a minimum number of parts in its construction; which iseasily assembled incident to installation on the door; and which,moreover, lends itself to ready.

manufacture at very small cost.

9 Other objects and attendant advantages will appear from the followingdescription of the attached drawings, wherein Fig. I is a view intransverse vertical section of a door embodying my improved latchmechanism.

Fig. II is a View like Fig. I showing themechanism in locked position.

Fig. III is a fragmentary view partly in elevation and partly in sectiontaken as indicated by the arrows III-III in Fig. I. l

" Fig. IV is a detail sectional view taken as indicated by the arrowsIV-IV in Fig. II.

Figs. V and VI are perspective views respectively of two parts which, inaccordance with my invention, together constitute the bolt actuatingspindle of the latch mechanism.

Figs. VII and VIII are perspective views of bushings respectively forthe outside and inside door knobs of the latch mechanism; and,

Fig. IX is a fragmentary perspective View showing how the components ofthe spindle are interengaged with a bushing whereto theoutsidemaniplating knob is secured.

With more detailed reference to the drawings,

45 l comprehensively designates a standard form of latch bolt unit whichis recessed into the swinging edge of the door 2, and which hasaprojecting beveled latch bolt 3 adapted to engage a keeper (not shown)on the door jamb. The

50 illustrated latch unit 1 maybe of any approved construction having acylindric body 4 with a face plate 5 at one end thereof through whichthesecuring screws 6 pass. The latch bolt 3 is op.- erable against springpressure in. a well known 55 way through suitable connections (not illusAnother aim of my invention is toattain thetrated) within the cylindricbody 4, by rotation of the hub indicated at 1.

Disposed at opposite sides of the door 2 in axial alig-nment with thehub 1 of the latch unit I and secured to the door by screws 8 and 9, are5 centrally-apertured circular escutcheons l0 and ii respectively havingoutwardly-projecting bosses l2 and [3 with socket recesses l4 and IS.The means for actuating the latch bolt 3 includes outside and insidemanipulating knobs I6 10 and I1 whichare shown as being of hollow sheetmetal construction with axial cylindric shanks l8 and]?! respectively.As shown,'the shank [8 of theoutside knob l6 fits into the socket recessM of the escutcheon l0, and secured within it 1 by spot countersunkconnections 20 is a bushing 2|. Similarly secured within the shank I9"ofthe inside knob II by spot countersunk connections 22, is a. bushing 23which has a dia metrically-reduced projecting portion 24 fitting into 20thesocket recess I5 of the escutcheon H. The knebs l6 and I! are held inthe assembly by a retaining element in the form of a fiat bar 25 ofoblong cross section which passes continuously through the door 2, thelatch hub I, the 25 escutcheons l0 and II, and the bushings 2| and23,.and which has lateral projections 26 and 21 at its opposite endswhich overlap shoulders afforded within the knobs by the remote ends ofsaid bushings. As shown in Fig. VII, the inner 30 shoulder end of thebushing 21 for the outside knob I6 is formed with steps as at 23, 29, 30and 3l, which, by placement of said bushing in different circumferentialpositions for selective coactiori with the projection 26 of theretaining bar 25, makes possible the adaptation of the latch mechanism.to doors of different thicknesses. Also extending continuously throughthe door 2, the latch hub l, the escutcheons l9 and l l and the knobbushings 2i and 23 is an 4) endwise slidable bar 32, which, like theretaining bar 25, is oblong in cross section, the cross sections of thetwo being so proportionedas to jointly fill the square opening .33 inthe. latch hub and the square axial opening 34 of corresponding size inthe bushing 21 of the outside knob 16. The bars 25 and 32 thus jointlyconstitute the latch operating spindle of the mechanism. The bore 35 ofthe bushing 23 of the inside knob I], it will be noted from Fig. so VIIIis cylindric, and as shown in Fig. IV of a diameterto clear the twospindle components 25. and 32. At its inner end, the shiftable spindlecomponent 32 is formedwith a push button head 36 which normally projectsoutward st through and axial opening 31 in the inside knob ll, see Fig.I. The bar 32 moreover has a pair of spaced projecting lugs 38, 39 atone of its corner angles adjacent the button head 36. As shown, the lug39 extends into a longitudinal groove 49 internally of the bushing 23 ofthe inside knob said groove being relatively wide as shown in Fig. IV soas to permit a limited amount of turning movement of the knob in eitherdirection on the spindle for a purpose presently explained. The lug 39is adapted to enter a notch 4| in the inside escutcheon II when thespindle component 32 is pushed inward of the knob H to the positionshownin Fig. II and thereby prevents operation of the latch bolt 3 by meansof the outsidefknob'IlG. Lodged within the internal grooveof the. insideknob bushing 23 is a leaf spring 42 with spaced offsets 43 which areadapted to cooperate with the lug 38 to prevent accidental displacementof the bar 32 in either of its two positions respectively shown in Figs.I and II. The bar 32 is held against withdrawal through cooperation of alug 44 on its head 33 with the inside of the outer wall of the knobafter passage through a notch in the latter. At its outer end, thebushing 23 of the inside knob I! has a double faced beveled camprojection 46 (Figs. I and VIII) which is normally aligned for coactionwith. a reversely-configured cam recess 41 (Figs. I, II and V) in theinner end of the button head 36 on the bar 32; said notch being ofgreater widththan the cam projection to permit slight independentrelative rotation of the inside knob as later on further explained.

The operation of my improved latch operating mechanism is as follows:

With the spindle component 32 positioned as shown in Fig. I, it ispossible to operate the latch bolt 3 by means of either the outside orinside knob l6, respectively, since the lug 39 on said component is atthis time withdrawn from the notch 4| in the escutcheon The mechanismmay be locked against operation from the outside with .the knob It bypushing upon the button head 36 of the bar 32 at the inside knob II,with the result that the lug 39 on said bar is engaged in the notch 4|of the inside escutcheon H as shown in Fig. II. The door 2 however maybe opened at any time from the inside by turning the knob Uponinitiation of the turning of the knob IT in one direction or the other,the bar 32 will be shifted rightward in Fig. II as a result of coactionof the cam projection 46 with the cam depression 41, in the inner end ofthe button head 36, until said bar 32 reassumes the position shown inFig. I with its lug 39 withdrawn from the notch 4| in the escutcheon Inthis connection it is to be noted that the width of the groove 40 in thebushing 23 of the inside knob I! is such asto allow the immediatelyforegoing action to take place before the side of the groove 49 engagesthe lug 39 to cause rotation of the spindle 32 as the knob I1 is turnedfurther in the same direction to operate the latch bolt 3. In order thatthe bar 32 may be shifted back to its normal position from Without thedoor, the knob I6 is provided with a slot 48 (Fig. I) for reception of asuitable key 49. Thus when the key 49 is inserted, its inner endencounters the bar 32 and pushes the latter rightward until the lug 39is disengaged from the notch 4| of the escutcheon l as in Fig. I, sothat the door can be opened by means of thejoutside knob Hi.

In assembling my improved latch operating assists mechanism, the latchbolt unit I is first mortised in the usual way into the swinging edge ofthe door 2. The bar 25 is next thrust into the knob l1 and its endprojection 21 hooked over the inner end of the bushing 23, and the bar32 thereupon inserted through the hole 31 in the knob until its forwardend is flush with the end of the knob shank l9. With this preparation,the escutcheon II is placed over the projecting end 24 of the bar 25 andthe latter pushed through the opening 33 in the hub 1 until theescutcheon rests against the door 2 and the knob bears against saidescutcheon. With the bar 25 still held tightly in place by the bar 32,the outside escutcheon I2 is run on and the knob l6 applied and itsbushing 2| hooked by engagement of the lateral end projection 26 of thebar 25 over the proper one of the step shoulders 28-3! of said bushing.The bar 32 is next run home and locked into position by turning theinside knob until the lug 44 has passed through the notch 59, where uponthe escutcheons Ill and II are finally ecured in place by the screws 8and 9.

Dismounting of the latch mechanism is effected simply by turning theknob I! to register its slot 50 with the lug 44 of the button 36 andthen withdrawing the latter and bar 32 whereupon the assembly will ofitself fall apart in an obvious manner.

Having thus described my invention, I claim:

1. Door latch mechanism comprising a latch unit with a latch boltoperating hub; inside and outside door knobs; and a lengthwise splitspindle of polygonal cross section fitting a correspondingly configuredopening through the latch operating hub, said spindle being formed oftwo bar components one of which is non-shiftable, said nonshiftablecomponent embodying integrally-formed means for interlocking the twoknobs, and means associated with the other component when shiftedendwise for looking or unlocking said knobs.

2. Door latch mechanism according to claim 1, wherein the spindlenon-shiftable bar component knob-interlocking means consist of lateralprojections from said component which engage over shoulders internallyof the two knobs to hold said knobs in place.

3. Door latch mechanism according to claim 1, wherein the door knobshave spindle engaging bushings; and the spindle non-shiftable barcomponent has lateral retaining projections which overlap the inner endsof the knob bushings to hold the knobs in place.

4. Door latch mechanism according to claim 1, wherein the door knobshave spindle engaging bushings; the non-shiftable bar component of thespindle has lateral retaining projections which overlap the inner endsof the knob bushinings to hold the knobs in place; and the inner end ofone of the knob bushings has steps providinga, number of shoulderswhich, upon placement of such bushing in different positionscircumferentially of the spindle, enable application of the mechanism todoors of different thicknesses- 5. Door latching mechanismaccording toclaim 1, wherein a member having a notch is fixed to the door, theshiftable bar component of the spindle extends through the inside knoband has a lateral lug, said lug, when the bar component is pushedinwards, engaging in the fixed. member notch to dog the spindle andthereby prevent operation of the latch bolt by the outside knob.

6. Door latchingmechanism according to claim 1,. wherein an escutcheonthrough which the spindle passes is secured to the inner side of theassists door, said escutcheon having a notch; the shiftable barcomponent extends through the inside knob and has a lateral lug, saidlug, when the bar component is pushed inwards, engaging the escutcheonnotch to dog the spindle and. thereby prevent operation of the latchbolt by the outside knob.

7. Door latching mechanism according to claim 1, wherein a member havinga notch is fixed to the inside of the door, the shiftable bar componentof the spindleextends through .the inside knob and has a lateral lug,said lug, when the shiftable bar component is pushed inward of saidinside knob, engaging in the fixed member notch to dog the spindle andthereby prevent operation of the latch bolt by means of the outsideknob; and the outside knob is provided with a slot for insertion of akey to release the spindle shiftable component for operation of thelatch bolt by means of the outside knob.

8. Door latch mechanism according to claim 1, wherein a member having anotch is fixed to the door, the shiftable bar component of the spindleextends through the inside knob and has a lateral lug, said lug when thebar is pushed inward of said inside knob, engaging the notch in thefixed member aforesaid to dog the spindle and thereby prevent operationof the latch bolt by the outside knob; and the inside knob includesmeans for coaction with the shiftable bar component whereby, uponinitiation of turning movement thereof, said component is unlocked topermit operation of the latch bolt by continued turning of the insideknob.

9. Door latch mechanism according to claim 1, wherein the outside knobis fixed upon the non shiftable spindle component; a member having anotch is fixed to the inside of the door; the shiftable spindlecomponent extends through the inside knob and has a lateral lug which,when said shiftable component is pushed inward of the inside knob,engages the notch in the fixed member aforesaid to dog the spindle andthereby prevent operation of the latch bolt by said inside knob, saidnotch being of a width to permit slight independent rotative movement ofthe inside knob on the spindle; and opposing cam surfaces, respectivelyon the shiftable spindle component and on the inside knob, cooperatingduring the slight independent rotative movement of said inside knob toautomatically withdraw the shiftable spindle component so that the latchbolt may be operated by continued turning of said inside knob.

10. Door latch mechanism according to claim 1, wherein the outside knobis fixed upon the nonshiftable spindle component; a member having anotch is fixed to the inside of the door; the shiftable spindlecomponent extends through the inside knob and has a lateral lug which,when said shiftable component is pushed inward of the inside knob,engages the notch in the fixed member on the door to dog the spindle andthereby prevent operation of the latch bolt by said inside knob, andsaid notch is of a Width to permit limited rotative movement of theinside knob in either direction on the spindle; and opposing camsurfaces, respectively on the shiftable spindle component and the insideknob, cooperate during the limited rotative movement of the inside knobin either direction, to automatically withdraw the shiftable spindlecomponent so that the latch may be operated by continued turning of saidinside knob in the same direction.

11. Door latch mechanism according to claim 1, wherein the outside knobis fixed upon the nonshiftable spindle component; a member having anotch is fixed to the inside of the door; the shiftable spindlecomponent extends through the inside knob and hasa lateral lug which,when said shiftable component is pushed inward of the inside knob,engages the notch in the fixed member on the door to dog the spindle andthereby prevent operation of the latch bolt by the outside knob; theinside knob having an axial bushing with an interior groove; theshiftable spindle component having a second lug which projects into thebushing groove, said groove being somewhat wider than the last mentionedlug to permit slight rotative movement of the inside knob in eitherdirection independently of the spindle; the bushing aforesaid having adouble faced cam projection, and the shiftable component having ashoulder with a reversely configured cam recess; and said cam projectionand. recess cooperating during the slight rotative movement of theinside knob in one direction or the other to effect automatic withdrawalof the shiftable spindle component so that the latch bolt may beoperated by continued turning of the inside knob in the same direction.

1 12. Door latch mechanism according to claim 1, wherein the outsideknob is fixed upon the nons'hiftable spindle component; a member havinga notch is fixed to the inside of the door; the shiftable spindlecomponent extends through the inside knob and has a lateral lug which,when said shiftable component is pushed inward of the inside knob,engages the notch in the fixed member on the door to dog the spindle andthereby prevent operation of the latch bolt by the outside knob; theinside knob having an axial bushing with an interior longitudinalgroove; the shiftable spindle component having a second lug whichprojects into the bushing groove, said groove being somewhat wider thanthe last mentioned lug to permit slight rotative movement of the insideknob in either direction independently of the spindle; the bushingaforesaid having a double faced cam projection, and the shiftablecomponent having a shoulder with a reversely configured cam recess; saidcam projection and recess jointly cooperate during the slight rotativemovement of the inside knob in one direction or the other to effectautomatic withdrawal of the shiftable spindle component so that thelatch bolt may be operated by continued turning of the inside knob inthe same direction; and a yielding member with spaced notches within thebushing groove to coact with the last mentioned lug to preventaccidental displacement of the shiftable spindle component in either ofits two positions.

RAYMOND HEIZMANN.

